Attended transfer timeout

hi,
i need to stretch the time for timeout on attended transfer.
when i transfer a call to other extension the timout is 15 second and i want more time.
i read that for this i need to set on /etc/asterisk/features_general_custom.conf

#######
txfernoanswertimeout = 105

but not work.

there are some setting for freepbx?
why?

You have the parameter misspelled, it should be

atxfernoanswertimeout = 105